shipping rates calculator for courier &amp;cargo php/mysql

I need a PHP/MySQL shipping rates calculator with exactly the same functionalities of this one [url removed, login to view] (I'll give you access to the sources of this) plus two added features:

1) an account system (username/password system) so that each user can add new custom couriers (such as UPS, FedEx, etc. with reserved rates) that will be shown mixed with the standard couriers when they are logged-in with their own account.

The new added couriers rates will be uploaded by them or by me via a CSV like that for standard couriers (see attachment).

Each user will have an own set of added custom couriers different/separated from the set of the other users.

2) the possibility for me (the admin) to limit what couriers of the standard couriers must be shown at user-per-user level (for example user1 sees USPS and DHL and not TNT, user2 sees USPS and not DHL and not TNT, etc.)

The source rates of the standard couriers are in the attached Excel file, that I convert to CSV and I can easily upload to MySQL to update the rates. The script to do this is already done for standard couriers but must be enhanced to support the separate upload of the users' couriers described in point 1